FBI, Federal Prosecutors Use Aggressive Tactics to Clean Up State, Local Politics

WASHINGTON—A string of federal corruption cases involving officials in Charlotte, N.C., San Francisco and other cities shows the fruits of an increased use of aggressive tactics by the Justice Department to root out state and local corruption.

In Charlotte, an undercover agent cultivated a relationship with an up-and-coming city councilman who became mayor, and allegedly gave him a briefcase filled with $20,000 in cash as a bribe. In...